Thermo-acoustic nuclear fuel rods could scream for help when stressed, preventing nuclear meltdown

It’s been more than three years since the Fukushima Daiichi power plant melted down, and despite nearly unlimited interest from the public we still have virtually no idea what’s going on in there. Detailed findings report the conditions immediately around the plant, beneath it in the soil, and above it in the atmosphere — but the core of the nuclear power station is so heavily shielded that its status remains largely unknown to this day. Experimental rad-shielded robots inch a bit further in every month, but their progress is slow. Scientists are desperate enough that they’re trying to make use of passing cosmic rays, which are occasionally powerful enough to pass through the core and ferry out some precious intel. But why are we just figuring this out now?

A new technology developed by academics and the Westinghouse nuclear company could keep this from being a problem in the future. When temperatures or pressures start to fluctuate, their new thermo-acoustic devices emit a corresponding auditory frequency that can be interpreted in real-time — it naturally whistles its status, in other words. Rather than use some complex monitoring rig that would fail in the intense environment of a working nuclear reactor, these thermo-acoustic sensors are based on passive physical forces. Changes in temperature, pressure, or even radiation dosage around the device cause natural shifts in resonant frequency — and thus, the tone of the whistle.

A simple diagram of the thermo-acoustic sensor.

By necessity, the design is as simple as can be. A resonator (long hollow rod) abuts a series of small parallel chambers called the stack. Temperature or pressure differentials across the stack, or changes in the rod’s physical shape due to intense radiation, produce predictable changes in the frequency of resonance inside the resonator — that frequency is our output information. This thermo-acoustic nuclear sensor uses 1100 parallel chambers made of a durable ceramic, and can be made small enough to fit virtually anywhere within the reactor core. Most interestingly, the team suggests that their monitors could be built into nuclear fuel rods themselves, turning fuel containers into sensors that intrinsically report changes without needing any outside power or supervision.

These simple devices would only be able to monitor one attribute of the core in one location, so an array of specialized thermo-acoustic sensors would be placed throughout the core to monitor different variables. Resonators of specifically tailored lengths and designs would produce a multi-voice chorus in a reactor, providing nuanced, real-time information with no need for energy input. If there’s any justice in the world, these scientists will at least try to tailor any “meltdown” frequencies to sound ominous and panicked, or perhaps like the monolith from 2001.

Stored nuclear fuel rods glow an eery, distinctive blue.

Regardless, if Fukushima had sported these devices from the start, we would almost certainly know much more about the state of its core today. The preference in nuclear engineering is now for these sorts of “passive” safety measures which rely on relatively fool-proof principles like thermodynamics. Ideas like “freeze plugs,” which require active cooling of a stopper which otherwise melts and totally drains the reactor due to gravity alone, represent the kind of fool-proof design we demand of nuclear technology these days.

While we of course want to keep watch for any cascading “meltdown” reactions, Fukushima’s nightmare scenario showed just how bad things need to get to foul up a modern reactor; the team sees their sensors as ultimately more useful to fundamental nuclear research. If a good portion of nuclear reactors were providing detailed records to some giant national database, analysts could probably derive useful suggestions for safety or efficiency upgrades.

This sort of functionality has been tantalizingly close for a while, being technically possible but infeasible in the real world due to costs and the high rate of equipment destruction. With simple designs like this, nuclear companies like Westinghouse could finally be able to look inside the fuel rods in an average nuclear plant directly and in real time. That’s the sort of upgrade you install quietly, hoping nobody notices that it wasn’t there all along.

actually we still need it if we want to have a good power/weight ratio or a power space ratio. if we ever colonize the moon or mars than we will use a nuclear reactor as the main power generator.

But we should close all our old reactors now and develop inherently safe reactors that cannot meltdown. just like the fusion reactors.

Ivor O’Connor

Maybe. However we don’t even make Plutonium-238 any longer. We were going to start making a very modest amount because it is getting difficult to buy it from the Russians. It takes something like 10 years to get the pipeline going. I think that was cancelled by our politicians this year. Then there was the project to make efficient use of the existing Plutonium-238 with something like a sterling engine that would give us 10x the power. That too was canceled by our politicians. As for normal reactors I don’t believe we have the water needed on the moon or anywhere else except a few moons to work them. And the power/weight ratio is not good for normal reactors.

massau

actually the latest tech or the opcoming they will use breading reactors we use uranium to create plutonium some isotopes have a very long half life (milions of years) this is used as a fuel for the next reactor.

and we end up with fission products that have a shorter half life and only a small percent will still have a half life of several 100 years.

Ivor O’Connor

These all power steam turbines that need water…

dc

There is water on Mars, at the poles. We know that. Maybe more underground.

Ivor O’Connor

Yes. You are right. My bad. Maybe more water in other places besides the poles. All frozen and locked away but perhaps perfect for a nuclear plant…

dc

Well it’s easy to melt if you have nuclear material. Science doesn’t consider some materials evil like political groups do.

massau

you only need a phase change material we use water because it is cheap on earth. but modern/next gen reactors will use molten salts in there main loop. but they can use a lot of materials in there second loop.

another way would be sterling engines or TEG.

Ivor O’Connor

Fine. And what do you use for the secondary and tertiary loops? You pretty much need water…

massau

i don’t know. but it would be a good initial power generator to be used at mars if we can build it from a lot of local materials.

otherwise we need to create a rocket that transports the reactor to there . which probably isn’t safe with today technology.

but the power density would be far greater than solar panels. the energy could also be used to produce the usable solar panels if there are the right materials on mars.

Ivor O’Connor

I guess it depends on many factors and “power density” seems to be just one factor. Solar panels seem to be the favorite and growing in popularity as each year passes.

“…A NASA-sponsored MIT think-tank has weighed up the future energy needs of a manned settlement on Mars and arrived at an interesting conclusion… …The MIT researchers assessed 13 different energy generation systems and compared solar and nuclear options… …a Mars mission should be able to transport several 2 metre-wide rolls of thin-film solar panel arrays. Rolling out an array of these thin-film rolls could supply ample energy to a colony. For example, if the array is positioned at 25° north, measuring 100×100 metres, 100 kilowatts can be generated. The MIT researchers even calculated it would take two astronauts 17 hours to construct the array (alternatively they could get a robot to do it).”

One could use a supercritical carbon dioxide or helium (and possibly even nitrogen) in a closed brayton cycle turbine. This cycle also produces high quality waste heat which on earth would normally be bottomed by a rankine cycle. On Mars, however one could use the heat for practical things, such as space heating, crop growing, or even ore processing.

Marc Guillot

Just say no to the old nuclear reactors, and build new ones of the latest generations.

Nuclear power is the safest and cleanest power generation that we have available at the moment.

Ivor O’Connor

New nuclear still produces waste. New nuclear would still be the most expensive. New nuclear would still require hidden subsidies in the form of military protection. And existing nuclear will vanish via attrition to be replaced by wind and solar.

Magnus Blomberg

LFTRS does not produce nearly as much waste as old reactors and can even “burn” the long lived waste already produced by old the reactors so we can get rid of it, producing lots of usable energy. That fact alone sould be enough to build some LFTR:s

Ivor O’Connor

Even if they did work as the dreamers wished they still don’t break up the energy monopolies controlled and protected by governments. Crony capitalism stifles technology.

massau

actually the governments should have never sold the reactor tech in the first place. secondly these reactors should have been build deep beneath the ground so it would be more safe.

Ivor O’Connor

Don’t know how I feel about your first point.

Second point though is a no go. Waste makes it’s way back no matter how deep we go. Look at Yucca Mountain. We thought we had something real there. Now we are stockpiling the waste on the sides of the nuclear power plants in the hopes we will either get a real solution or the political climate will change and we can hide the stuff in some hole.

massau

i meant that a bunker reactor design will not get something like Chernobyl.
if it is beneath the ground water than it will have less consequences than on the surface.

Ivor O’Connor

There is always something wrong they are trying to hide. The problems are usually, always, the plants are not making enough profit and so they don’t have the money to properly train and run safety drills. Since most all of our nuclear plants here in America are leaking there is no way they would ever agree to being underground. There would be nowhere to hide the leaks.

bober9989

Greentard getting btfo^

LeanieMorisonycu

Josiah . although Jacqueline `s stori is surprising,
last week I bought themselves a Chrysler from having made $5060 thiss month
and-in excess of, 10/k last-month . it’s realy the easiest-work I have ever
done . I started this 4 months ago and pretty much straight away was bringin in
at least $78 per-hour . why not look here C­a­s­h­d­u­t­i­e­s­.­C­O­M­

Pat D.

Chernobyl’s RBMKs were such a terrible design that its a bad example for just about anything. And even then, it took a near comedy of errors for the disaster to occur.

dc

We need to push geo-thermal. It’s clean and basically limitless. Nuclear will always be around to some extent as the military needs it for weapons. Also they need it to power large ships and submarines.

massau

what happens if the core of our planet cools down especially if every country starts to use it? i think we will have much worse problems when we use it.

sketchbag

Nuclear can be entirely clean and very safe. Just not reactors from the 60s, 70s, etc. Thorium might be one answer, fusion another. But carbon-dioxide producing power generation is slow and steady killing, nuclear reactors based on uranium are low risk, high impact type. both are bad. until we can harvest solar or fusion in massive quantities, all manufacturing will be largely fossil fuel anyway. Your car or house might be electric-by-solar, but the solar panels will be built and shipped by coal or oil. we need better batteries, and nuclear (even fission) in the mean time in place of the co2 outputters.

Ivor O’Connor

So you are basically saying all the reactors in the USA are inherently dangerous. Unfortunately they are too expensive to rebuild. They are also too expensive to maintain. Hence we will be seeing many more closed.

Solar and wind are growing at about 30% per year. That is not much when it was .001% of the total energy. Now however they are on the scoreboard and it won’t take but two or three decades before they dominate all energy sources. It is all about price.

massau

solar and wind alone are not the solution until we have batteries or a good way to store them, like a hydro dam. today we will have bad luck if there is no wind at night.

or we need to use oil or coal as the main power source. but that will just use massive amounts of fuel per day.

Ivor O’Connor

Right now we have such over capacity at night places like Texas are giving away the electricity free. Less costly to turn it way down and give it away than restart. Other power companies pay to have their energy dumped into huge banks of resistors. They figure it sets a bad precedent to give electricity at night away for free. We do not have to worry finding electricity at night when the sun does not shine. For a long time.

In two or three decades when solar and wind have replaced crony capitalism we will have built HVDC lines. With HVDC lines we can pump in the power at night from wherever the wind is blowing. HVDC can transport power for thousands of miles efficiently. There may also be solar thermal plants that have 24×7 power primarily for feeding the night time users. Or batteries may used if hundreds of giga factories become a reality as planned. Or methane generated by wind and solar for overnight use in traditional gas power plants.

massau

the energy they give away is actually the energy that is generated bu nuclear power plants at night. you cannot shut them down at night.

but i like the idea of using DC instead of AC in the future. it would also give us a window to higher the net voltage (300V) and thus lower the wasted energy in the network itself. maybe we could finally use an universal socket around the planet.

Ivor O’Connor

Not just nuclear. “Base load power plants operate at maximum output. They shut down or reduce power only to perform maintenance or repair. These plants produce electricity at the lowest cost of any type of power plant, and so are most economically used at maximum capacity. Base load power plants include coal, fuel oil, almost all nuclear, geothermal, hydroelectric, biomass and combined cycle natural gas plants.”https://en.wikipedia.org/wiki/Load_following_power_plant

Iv seen it discussed that Thorium was known about but was ignored because it does not produce waste that is fissile. Sad that so many years of progress were wasted for the arms effort.

gd

Just say no power then. WIthout nuclear, all we have are dirty fossil fuels, and inefficient renewables.

Justin

“These simple devices would only be able to monitor one attribute of the core in one location, so an array of specialized thermo-acoustic sensors would be placed throughout the core to monitor different variables.”

Just seems like they are already monitoring all the variables that would lead to a change in accoustic vibration. When you have multiple systemic failures you get Fukushima.

eonvee375

no need, fusion is near ^^
jk, every upgrade is a good one ^^

wfs

So when the rods “scream for help” we will assume those humans responsible for responding to the “screams” are not themselves screaming for help? Prevention of a meltdown is similar to prevention of a plane accident. If its up in the air it will come down. Humanity is nowhere near perfect and therefore incapable of “preventing meltdowns” 100% of the time. Go to a bookie you don’t need a scientist to figure that one out. Oh earthquake tsunami. glad the rods are screaming. lets harmonize together.. ready EEEEEE LLLLLLLL EEEEEEE

Jonathan Abbey

Fukushima was not a modern reactor.

jcaunter

You should explain that to Obama, who recently approved several additional Fukushima-style reactors to be built in the US. Yes, the same GE design used in Fukushima. Therefore it’s modern, right?

Pat D.

Just because a reactor is BWR and made by GE does not mean it wouldnt have 40+ years of enhancements in safety technology and control systems, or that the overall design of the plant would be comparable to the older cores that melted at Fukushima.

Ivor O’Connor

I doubt any of them will actually be built. Even if the politicians pay for the land, for the building of it, the insurance, the management of waste, and for the plant closure sometime in the future. They are just too expensive and no sane company wanting to make a profit will touch them.

Ivor O’Connor

Nor are any of the reactors in the USA.

Jason

The accident in Fukushima was due to operator error. If they had allowed the system to vent the Hydrogen gas to atmosphere the core would have melted but stayed in it’s vessel. Instead they vented Hydrogen inside the reactor building it then exploded like hydrogen does and cracked the containment vessel leaking the very water the system needed and contaminating the building. The actual fuel is contained in the fail safe foundation under the building and did not reach the soil.

massau

they should have made the reactor so it would have been physical impossible to vent in the hydrogen. this would really make the reactor fool proof.

jcaunter

“Fukushima’s nightmare scenario showed just how bad things need to get to foul up a modern reactor”

If that’s the “lesson” you’re taking away from Fukushima, then you all are completely and utterly insane. Fukushima showed how easy it was for reactors to melt down; not how difficult. How dumb do you think we are?

Pat D.

Whoa….hold on a second…a 9.0 magnitude earthquake and Tsunami hit the plant…thats just a little bit unusual, no?

jcaunter

No. Because their models showed the such an event had such little likelihood of happening that the possibility was effectively zero. And therefore they proceeded as if possibility were zero. However, these people did not and still do not understand the nature of complexity, risk, and multiple interdependent systems. Nassim Taleb’s book “Black Swans” is where these morons should have been developing their risk models from. Instead they went with the standard, and wrong, value at risk (VAR) model.

According to Talebi’s risk model based on actual reality, more nuclear plants melting down all over the place is a near certainty, and Fukushima is not a one-off, but a harbinger.

Pat D.

And yet, it took a historically amazingly powerful force of nature and operator error for these melts to occur.

I’m not a fan of saying “We’re due for a disaster!”—its a terrible way to live your life. Aren’t we also due for a monstrous earthquake to send the West Coast to the bottom of the ocean? Or (another) large asteroid to strike the earth?

gd

I assume the likelihood of a disastrous earthquake hitting your house is unlikely. Thats why you live there. When a sudden unpredictable event does hit your home, we’ll be sure to leave you buried under.

“Fukushima is not a one-off, but a harbinger.”
There are about 435 nuke reactors worldwide, operating since the 1950s. So, yes, Fukushima is a one-off.

Ivor O’Connor

Thank you for pointing out that subtle propaganda. It’s crap like that you don’t immediately recognize that gets into your subconscious and soon you think it is ok. The author should have a finger cut off for trying to get away with this!

Sam Cerulean

The level of apathy and media attention Fukushima has got is staggering. This has had a catastrophic effect on wildlife and especially the ecology of sea life around the world. Fish levels are the lowest they’ve been for about 40,000 years and nobody wants to recognise the damage that’s been done and how dangerous nuclear power really is.

Forget all the recent disasters of the last decade, the long term effects are worse than all of these events combined and I’m sure will come to realize how detrimental the radiation from Fukushima really has been years from now.

massau

Fish levels are the lowest they’ve been for about 40,000 years and
nobody wants to recognise the damage that’s been done and how dangerous
nuclear power really is.

really this is not because of the nuclear reactor it is caused by our fishing behavior. We fish up a lot of fishes but we only take the best kinds like salmon the lesser known types are just thrown back into the sea dead.
Also trawlnets are still used which damadge the bottom of the ocean and thus destrooying the habitat of the fishes.

Sam Cerulean

Although that is true there have been massive shoals of fish and other marine life dying for explained reasons all off the world for the last 2 years.
Just look it up and you’ll see the magnitude this has been happening.

Christopher O’Loughlin

Graham T,
Thank you for writing about Fukushima 3/11. Muon Energy Location Technology MELT has located three reactor cores below the broken leaking reactor vessels in Fukushima. TEPCO is building an underground Ice Wall to try and contain the radioactive water running over the melted cores flowing down hill to the beach a few hundred yards away. Westinghouse BW reactor’s designed for and sold to TEPCO suffered three separate reactor core meltdowns at Fukushima on 3/11
Graham, three reactor core meltdowns are known to have occured on 3/11. The world has accepted that reality. Today 6/13/14 the world is waiting for TEPCO to release the MELT reactor core location findings. Don’t hold your breath. Once the MELT location information is released the phase of removal may begin. TMI BW reactor core melt down took over six years to remove once removal process began. TEPCO is not planning on releasing MELT reactor core location for years. Multiply TMI known experience with reactor core meltdown removal timeline by three then we are facing an 18 year removal process. Don’t forget about the possibility of accidents during core removal process which could delay beyond 18 years. Facing this decades long radioactive site clean up of Westinghouse BW reactor core meltdowns in Fukushima do you really think Westinghouse should be designing technology that will scream so location will be known after meltdown is the most helpful utilization of Westinghouse design expertise?

Barry

Fukushima radiation in fish and seafood is growing worse and its going to keep getting worse as TEPCO the Japanese nuclear power company continues to dump millions and millions of gallons of radioactive poison into the Pacific ocean each and every day! Depending on the ocean currents and fish migrations some fish will be much more radiated then others! YES PEOPLE it is to the point that people that have been eating Pacific ocean fish and seafood should now seriously consider doing a radiation detox with the natural mineral called Zeolite that has been proven to safely remove both radiation and toxic heavy metals from the body! For more information on this important detox do a simple online search for the single word Zeolite.

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